This invention relates to recycling systems and methods including apparatus which is generically described as a tub grinder. Such machines, which may also be referred to as waste wood recyclers, are used today to convert stumps, brush, pallets, ties, large timbers, demolition debris, old dead trees, old lumber piles and the like to particulates which are useful, for example, as mulch, ground cover, material which can be used as a bulking agent for composting sewage sludge, and as fuel for high temperature incineration systems which generate processed steam. Such systems are a cost effective alternative to the land filling of the bulky material, which is expensive and uses up huge tracts of land adjacent municipalities which are better used for other purposes. Typically, tub grinders have utilized hammermills for the purpose of grinding the material to a particular size to provide material suitable for composting, erosion control, boiler fuel and landscaping ground cover. Such hammermills have been relatively short-lived and expensive to maintain. Typically, they have been used to process small stumps and material up to twelve inches in diameter, but have not been, to my knowledge, used for much heavier wood waste.